(N/A) The total number of degrees of freedom in a thermodynamic system is given by the product of the degrees of freedom per molecule and the total number of molecules.
At $NTP$,the volume occupied by $1$ mole of an ideal gas is $22400$ $cc$.
Using Avogadro's number $(N_A = 6.023 \times 10^{23})$,the number of molecules $(n)$ in $1$ $cc$ is:
$n = \frac{6.023 \times 10^{23}}{22400} \approx 2.688 \times 10^{19}$ molecules.
Hydrogen $(H_2)$ is a diatomic molecule. At room temperature,its degrees of freedom $(f)$ is $5$ ($3$ translational + $2$ rotational).
Total degrees of freedom $= f \times n = 5 \times 2.688 \times 10^{19} = 1.344 \times 10^{20}$.